Carbonizing apparatus



(No Model. v 2 Sheets--Sheet 1.

No. 511,459. Patend Deo. 26, 189s.

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I. L. ROBERTS.

GARBONIZING APPARATUS.

INVENTOR ATTORNEY Patented Deo. 26, 1893.

WITNEssEs:

UNITED STATES PATENT OFFICE.

ISAIAH L. ROBERTS, OE BROOKLYN, NEW YORK.

CARBONIZING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 511,459, dated December 2S, 1893.

Application filed December 8, 1892. Serial No. 454,541. (No model.)

T0 all whom it may concern:

Be it known that I, IsArAH L. ROBERTS,- a citizen of the United States, residingin Brooklyn, county of Kings, in the State of New York, have invented a new and useful Electric Process and Apparatus for Baking Carbons; and I do hereby declare that the followingis a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to construct and use the same.

Heretofore carbons have been pressed in molds or dies, and placed in an oven or furnace and slowly heated for many hours and even days, in order to completely decompose and carbonize the binding material. In this practice much time and fuel are lost, while the metallic boxes or other receptacles in which carbonization takes place, are rapidly oxidized or 1n case of earthenware, soon broken.

The object of my invention is to apply heat electrically to the carbon in such a manner that the wear on the apparatus will be lessened, fuel saved and the time shortened in ca'rbonizing the binder. In order to accomphsh this, I construct an apparatus shown in Figures l, 2 and 3.

Fig. l is a plan partly cross-section of the apparatus when in operation. A and B are the two parts of an iron clamp. B slides on the lower portion of A, and is moved back and forth by the lever L and held in place when tightened by the movable wedge M, which rests against the stop N. O and D are tire clay slabs made fast to their respective jaws of said clamps by counter-sunken bolts a a o, a. These fire clay slabs are faced with heavy asbestus 7L h, the whole being wide enough to take in the'iron box, Eig. 3 and close tightly against its sides and bottom.

Fig. 3 shows a vertical cross section ot` an iron box preferably perforated on its sides and bottom Il H and closed at the ends by heavy masses of iron O O. These bars or masses of iron are tipped with copper connectors S S brazed on at P2P2. PP are couplers for connecting the conductors S S. The sides and bottom of the box are made of thin sheet iron, though other metals which will stand a high heat may be used. The sheetiron should be made fast to the massive ends by being welded, cast or screwed on with. small `the figures are carbons.

screws near together as possible, so as to cause or secure as good contact as possible as at T T, Fig. 2. This box should have a partition, if a large number of carbons are to be baked at once,or many partitions may be used. They should be of the same or near the same electrical resistance as the sides and bottom, for equal surface and cross'section. The partition is shown at J, Figs. l and 3. I I in all K K is sand filled in around the carbons tc prevent air reaching them while hot.

To operate my process and apparatus I proceed as follows: I take as many carbon articles pressed or molded in the usual and well known way, electric arc light pencils for inlstance, and stand them on end in a single row on each side of the partition J, Figs. l and 3, leaving a small space between each other and the partition and Walls of the box. I now fill the spaces so left with sand, coarse enough not to fall through the perforations. I make 'the said box high enough to permit ofcovering said carbons about two inches. I then place the box and carbons in between the jaws of the aforesaid clamping device, and force them together and lock them. The heavy masses of iron O O and copper connectors S S project outbetween the inclosing jaws, but the asbestus facings h 71, of the fire clay slabs cover the perforated sides completely. I then attach the connectors P P to a source of electricity of suliicient strength to heat the thin sides, bottom and partition to a white heat. I prefer to apply the current slowly so as to drive off the gases which are liberated at a low temperature first and gradually raise it, until the box and contents are white hot. It the heat is too suddenly raised the carbons will be porous and soft. When allowed to cool until danger of oxidation is passed, the box may be removed and another substituted. The conductivity of the end masses of iron should be a great many times greater of cross section than the total metal in the sides, bottom and partition, so that they will not become so hotand waste the current. The use of the partition is to get a uniform heat on both sides ot' the carbon which will prevent them from bending from unequal contraction when carbonizing.

The box is perforated for the purpose of IOO allowing .the reducirghydrorcarbcngases, t0 escape outside and unite with any oxygen present next tothe asbestus, and thus protect the box from destruction at such high temperatures as are used.

The Object 0f. the. 11S@ of ashestus ,is t0 ft closely to the sides of the box and tiii's'ulte the heat thus causing it to remain next to the box. I use fire clay slabs also because they are firm and at the same time conduct the heat poorly. The sand in the box is used for the purpose of preventing the carbons freni sticking to each other or the box While carbonizing; also to prevent air froxii getting yto thekhot carbons and for holding them firmly in .position While carboning thebinder and ngi; g horens wm antw the gases e) @Stap-l uesf @heffing or erbeten iisi'sts in placing the articles ftfo be lent. then `lasting a .nrrenwfelilffilicity through a conductor iii contact with said mass.

2. An apparatus for charring or carbonizing by the heat of the electric current, Whlch consists of a vessel that is a conductor of electricity. said vessel beingA held by aclamp faced with a ixible facing', such as asbestus.

3. The combination of a perforated electrically conductive vessel and an outer noncon'ducting covering. y

4. A box or vessel for containing substances to be carbonized which has one or `more conducting diaphragms through it, in the manii'er and foi' the purpose described.

5. A box or ,vessel which is a contuetorl of electricity, and -vvlii'li has cl'palatively lilas# vsive ends, which eiidspare' fastened tli cto; in the nia-nner and fll e de lribell.

Y IsAInH L. ROBERTS.

Witnesses; Q

R. V. SHLTR. 

